System and method for altering pacing modality

• US 7,515,958 B2
• Filed: 07/31/2006
• Issued: 04/07/2009
• Est. Priority Date: 07/31/2006
• Status: Active Grant

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Sheldon, Todd J., Betzold, Robert A., Sweeney, Michael O., Hettrick, Douglas A., Stanslaski, Scott R.
• Primary Examiner(s): Evanisko; George R
• Assistant Examiner(s): PATTON, AMANDA K
• Application Number:
  US11/461,111
• Publication Number:
  US 20080027496A1
• Time in Patent Office: 981 Days
• Field of Search: 607/4, 607/9, 607/14
• US Class Current: 607/9
• CPC Class Codes: A61N 1/3622 comprising two or more electrodes co-operating with different heart regions
• CPC Class Codes: A61N 1/3688 configured for switching the pacing mode, e.g. from AAI to DDD

Abstract

An implantable medical device operates according to a ventricular pacing protocol (VPP) that precludes ventricular pacing in any cardiac cycle where a sensed ventricular event has occurred in the preceding cycle. Improved ventricular sensing, detection and classification is provided.

Claims

1. A method comprising:

operating an implantable medical device (IMD) in a ventricular pacing protocol (VPP), wherein the VPP is a pacing protocol that tolerates a complete cardiac cycle devoid of ventricular activity while providing for ventricular pacing in the cycle immediately subsequent to the cardiac cycle devoid of ventricular activity;

sensing for ventricular arrhythmias;

determining if a correlation between ventricular pacing in the VPP and the sensed ventricular arrhythmia is present;

discontinuing the operation of the IMD in the VPP if a correlation is determined to exist.

2. The method of claim 1, further comprising:

determining if a ventricular pace preceded the sensed ventricular arrhythmia within a predetermined number of cardiac cycles; and

continuing to the step of determining if a correlation exists only if there was a ventricular pace within the predetermined number of cardiac cycles.

3. The method of claim 2, further comprising:

determining that the correlation exists only if there was a ventricular pace in the cardiac cycle immediately prior to the sensed ventricular arrhythmia.

4. The method of claim 3, wherein determining that the correlation exits further requires sensing a premature ventricular contraction (PVC) in a cardiac cycle immediately prior to the cardiac cycle wherein the ventricular pace was delivered.

5. The method of claim 1, further comprising:

determining if a ventricular pace preceded the sensed ventricular arrhythmia within a first predetermined number of cardiac cycles;

determining if a premature ventricular contraction (PVC) occurred in a cardiac cycle immediately prior to the cardiac cycle wherein the ventricular pace occurred; and

determining that the correlation exists if there was ventricular pace that was preceded by a PVC.

6. The method of claim 5, wherein determining if a PVC occurred further comprises:

evaluating data sensed on a ventricular channel; and

obtaining data from a secondary source if the ventricular channel data does not indicate a PVC and determining if the data from the secondary source indicates a PVC.

7. The method of claim 5, wherein determining if a PVC occurred further comprises:

evaluating events sensed within a crosstalk window to determine if a pattern is present; and

classifying an event sensed in the crosstalk window as a PVC if there is no pattern present and classifying the event as crosstalk if there is a pattern present.

8. The method of claim 7, wherein if there is insufficient data to determine if a pattern exists, then the IMD continues operation in the VPP to gather additional data.

9. The method of claim 1, wherein the IMD is changed to operate in a DDD mode.

10. The method of claim 5, wherein a correlation is determined to exist whether or not a PVC occurred in the cardiac cycle immediately prior to the ventricular pace.

11. An implantable medical device comprising:

means for operating the IMD in a ventricular pacing protocol (VPP), wherein the VPP is a pacing protocol that tolerates a complete cardiac cycle devoid of ventricular activity while providing for ventricular pacing in the cycle immediately subsequent to the cardiac cycle devoid of ventricular activity;

means for sensing for ventricular arrhythmias;

means for determining if a correlation between ventricular pacing in the VPP and the sensed ventricular arrhythmia is present; and

means for discontinuing the operation of the IMD in the VPP if a correlation is determined to exist.

12. The IMD of claim 11, further comprising:

means determining if a ventricular pace preceded the sensed ventricular arrhythmia within a predetermined number of cardiac cycles and continuing to determine if a correlation exists only if there was a ventricular pace within the predetermined number of cardiac cycles.

13. The IMD of claim 11, further comprising:

means for determining if a ventricular pace preceded the sensed ventricular arrhythmia within a first predetermined number of cardiac cycles; and

means for determining if a premature ventricular contraction (PVC) occurred within a second predetermined number of cardiac cycles prior to the ventricular pace and continuing to determine if a correlation exists only if there was a ventricular pace within the first predetermined number of cardiac cycles and there was a PVC within the second predetermined number of cardiac cycles.

14. The IMD of claim 13, further comprising:

means for evaluating events sensed within a crosstalk window to determine if a pattern is present; and

means classifying an event sensed in the crosstalk window as a PVC if there is no pattern present and classifying the event as crosstalk if there is a pattern present.

15. The IMD of claim 11, further comprising means for providing a first post a trial blanking period (PAVB) having a first duration and second PAVB having a second duration, longer than the first duration wherein the second PAVB is utilized only after a ventricular pacing pulse has been delivered and the first PAVB is utilized whenever ventricular pacing has not been provided within a predetermined period of time.

16. An implantable medical device (IMD) comprising:

a cardiac pacing module to sense cardiac data and selectively provide cardiac stimulation according to a ventricular pacing protocol (VPP), wherein the VPP is a pacing protocol that tolerates a complete cardiac cycle devoid of ventricular activity while providing for ventricular pacing in the cycle immediately subsequent to the cardiac cycle devoid of ventricular activity;

an arrhythmia determination module to determine if a ventricular arrhythmia occurred based upon the sensed data;

a mode selection module to discontinue operation in the VPP if the module determines that a probable causal correlation between a ventricular pace delivered according to the VPP and the ventricular arrhythmia is present.

17. The IMD of claim 16, wherein the probable causal correlation is established if the ventricular pace immediately preceded the ventricular arrhythmia.

18. The IMD of claim 17, wherein the probable causal correlation is established only if a premature ventricular contraction (PVC) occurred in the cardiac cycle immediately prior to a cardiac cycle wherein the ventricular pace was delivered.

19. The IMD of claim 18, further comprising:

a PVC identification module that evaluates ventricular data occurring during a crosstalk window and determines that the data indicates a PVC if no repetitive pattern exists over multiple cardiac cycle and determines that the data is crosstalk if there is a repetitive pattern.

20. The IMD of claim 18, further comprising:

a secondary data module that obtains and evaluates ventricular data from one or more sources other than a ventricular channel when the data from the ventricular channel does not indicate a PVC within the second predetermined number of cardiac cycles.

21. The IMD of claim 16, wherein the mode selection module continues to operate the IMD in the VPP until multiple ventricular arrhythmias have occurred with a probable causal correlation to ventricular pacing.